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Power supply and electrical equipmen
Improvement of the Design of a Sectional Insulator
Tarabin Igor, Titova Tamila, Terekhin Ilya, Rummo A.A.The object of research is a sectional DC insulator. The purpose of the work is to improve the technical performance, design, installation and operation process. Research methods - empirical, theoretical. The results obtained can be used in accordance with data standards for the production of sectional insulators. Degree of implementation: a design for improving the sectional insulator has been developed
Keywords: сontact network, sectional insulator, polymer insulator, hydrophobicity, safety measures, carrying cable, power supply distanceModern protection and automation of the installation of a longitudinal capacitive walk-through traction substation
German Leonid, Serebryakov Alexander, Dulepov Dmitry, Osokin Vladimir, Petrov DenisInstallation of longitudinal capacitive compensation (ILC) on 27.5 kV buses compensate for the resistance of the traction transformer and the external power supply system, and theoretically, with any traction load, it is possible to obtain voltage close to the idling of the power source on traction buses. Superfast protection on thyristor switch (TS) is installed on ILC. With the help of mathematical modeling, it is proved that in order to significantly reduce dangerous overvoltages on capacitors in emergency situations, the command to start the thyristor switch should be transmitted via the short-circuit current, which minimizes the duration of the flow of powerful short-circuit currents. Thus, ILC protection from short-circuit high-power currents should be performed using thyristor switch with short-circuit current start, and at remote short-circuit currents in the traction network, limitation of ILC short-circuit currents occurs when the thyristor switch is triggered with start-up by ILC voltage with subsequent disconnection of short-circuit currents. It is proposed to perform overload protection of the ILC capacitors using thyristor switch with starting by the ILC voltage and with relay with a dependent time delay. After shunting the ILC with thyristor switch, it is possible to determine the failure of capacitors after short circuit by unbalanced protection, and then the question of whether it is advisable to re-activate the ILC in operation should be resolved
Keywords: longitudinal capacitive compensation, superfast protection, automation, start of thyristor by current, overload of capacitors, re-activationUneven load distribution between the rectifier units
Chervonchenko Sergey, Frolov VladimirParallel operation of the rectifiers is necessary when the load is high power, as well as a high category of consumer reliability. However, for the successful operation of the equipment in this mode, several important conditions must be met, namely: the equality of the output voltages, the rated power and the number of ripples of the rectified voltage. If at least one of the above conditions is not met, the load begins to be distributed unevenly between the rectifier units, which negatively affects the equipment. The article presents a mathematical model of a real electrical network in the MATLAB/Simulink software package. Graphs of the power distribution over the rectifier units depending on the input voltage to the rectifier are obtained. As a result, it can be concluded that for parallel operation, it is necessary to choose equipment with the same internal characteristics not only for transformers (short-circuit voltage, rated power), but also for the rectifiers themselves (diode resistance)
Keywords: rectifier unit, transformer, parallel connection, mathematical modeling, load distribution, powerDevelopment of a generalized graphic-analytical model of the subsystem for monitoring and controlling the electricity supply system of the subway
Kanaev Andrey, Davydova Anastasia ValentinovnaThe need to develop a generalized graphic-analytical model is due to the lack of functionality of the existing subsystem for monitoring and controlling the electricity supply system of the subway to analyze the process of functioning of the power supply system as a justification for structural optimization. The applied method of generating functions and graph theory determine the ratios for the probability of recovery, recovery time and the required amount of diagnostic tools, which are important for substantiating the assessment of the degree of achievement of the requirements, which makes it possible to make a correction of the decision to modernize the object under the conditions of specified requirements and restrictions
Keywords: monitoring system, graph, generating function, recovery probability, electricity supplyState of Function of the Three-Phase Rectifier of an Automobile Alternator
Puzakov Andrey Vladimirovich.One of the main causes of failure of automotive alternators are diodes faults in the rectifier unit. Relevant is the task of determining the technical condition of the vehicle alternator (including the rectifier) based on the on-board monitoring of output voltage parameters. Analytically rectifier voltage at open circuit of one or several diodes is represented as a sum of terms, corresponding to the time intervals of rectifier operation. A technique for modeling diode open circuit of a three-phase bridge rectifier is presented. It is experimentally proved that output voltage of the rectifier is determined by the number of diodes involved. It is proposed to calculate the rectifier's degree of functioning as the ratio of the current voltage value to the voltage of the rectifier in good condition at the same current value. Generalized model of three-phase rectifier voltage will be used for development of measuring complex of onboard monitoring of vehicle power supply system
Keywords: automotive alternator, Three-phase rectifier, Diode open circuit, Fault modeling, State of FunctionSpecialized microcircuits for active battery balancing devices in autonomous power systems
Zuev Sergey, Varlamov DmitryThe article presents a description of the main parameters that describe the state of battery systems. Specialized microcircuits for active battery balancing devices in autonomous electric power systems are considered. The advantages of three types of microcircuits for active balancing control, which are recommended by manufacturers for use in traction batteries of electric transport systems, are considered. Based on the results of the work carried out, the following conclusions can be drawn that active battery balancing devices have significant advantages over passive balancing devices. But they have a greater complexity of the power circuit and cost. The balancer power circuit from AustriaMicroSystems has no battery capacity limit, but it is less efficient than the Linear Technology balancer power circuit. The Texas instruments device is the simplest in its design and application algorithm, but its disadvantage is that its power circuit is inefficient for large batteries, so it is recommended only for use in electric scooter batteries and similar devices
Keywords: microcircuit, active balancing devices, storage batteries, electric power system, algorithmApplying energy storages as emergency power supply system at underground railway trains
Kuznetsov GrigoryThe purpose of this work is to describe the existing design of subway cars of models 81-775/776/777 "Moscow-2020", which includes the use of traction energy storage devices for use in emergency situations, as well as during shunting operations
Keywords: railway transport, subway cars, energy storage, nickel-cadmium storage battery, traction electric machinesAn alternative control algorithm for the power converter of an AC electric locomotive in emergency modes
Skorik Vitaly Gennadievich, Suprun Demian Andreevich, Malysheva Olga AlexandrovnaThe article considers the characteristic features of the flow of electromagnetic processes in the event of loss of control of reversible converter`s arms used in AC electric locomotives with collector motors. An alternative algorithm for controlling the converter in the first and second voltage regulation zones is proposed. Mathematical modeling of electromagnetic transient processes in the circuit of electric locomotive engines has been carried out. The analysis of modeling for normal and emergency modes of operation of the converter is carried out
Keywords: AC electric locomotive, reversible converter, arm break, alternative control algorithm, control systemTrends in the development of electronics and electrical equipment on vehicles
The use of on-board energy storage devices in urban rail transport
Sharyakov Vladimir, Sharyakova Olga, Markov KirillThe modern electrical base makes it possible to increasingly abandon the use of solid fuels and switch to electric transport. The problem that arises during the operation of electric rolling stock is its non-autonomy. In this paper, we propose the results of the introduction and testing of an electric energy storage device consisting of capacitor modules in urban transport. As a result of connecting one of the tram trolleys of the accumulator to the power circuit, its positive effect on the operation of the drive was established. It was possible to achieve a reduction in the average current consumption, significantly reduced the consumption of electricity for traction
Keywords: electric energy storage, electric rolling stock, urban electric transport, traction electric drive, electricity consumptionDiagnostics and testing
Application of computational methods in forecasting the heat load
Vasiliev AlexanderIn recent years, reducing energy costs and CO2 emissions have become major factors in production management. For this reason, the energy market is showing increasing interest in highly efficient generation management at CHP plants. One way to reduce the environmental footprint without sacrificing performance is to implement energy management systems: intelligent devices that can ensure that generators run at an optimized time using forecasts of load for the following days as input. Forecasting the load on electricity is an important task in the context of the restructuring of the power system for successful power trading in energy exchange and business activities. This paper explores the application of computational methods that allow predicting the consumption of thermal energy, based on the ambient temperature. A regression-based technique is proposed to create numerical models that capture the relationship between temperature and heat energy consumption. The methodology has been successfully tested on measurements taken at an operating CHPP in the Far East - The results show that the methodology is able to predict the consumption of thermal energy and, therefore, can help in predicting the consumption of resources
Keywords: machine learning, energy, linear regression, algorithm, model, electricityStructural-parametric synthesis of the control system of the electrical complex of the lifting mechanism
Domanov Viktor, Murzakov DmitrijThe structural synthesis of an induction motor with a wound rotor control system of the lifting mechanism included in the electrotechnical complex (ETC) is carried out. The main elements of the control system are defined. A computer model has been developed to evaluate transients. The calculation of the corrective links of the subordinate control system (speed and torque regulators) providing the required characteristics is performed. When solving the tasks, computer modeling methods implemented in the SimInTech dynamic modeling environment, the theory of automatic control and the theory of electric drive are used. The proposed structure of the two-channel WRIM control provides a shock-free transition from the nominal speed to the holding mode, thereby ensuring that the requirements for minimizing jerks of the lifting mechanism are met
Keywords: wound rotor induction motor, lifting mechanism, holding mode, subordinate regulation, WRIM model, differential selsyns, dual power supply